#216 : High Live Birth Rates After Low Dose Lymphocyte Immunization Therapy (LD-LIT) with Partner Lymphocytes in Recurrent Miscarriage Patients

Abstract

Background and Aims: Recurrent Miscarriage (RM) affects 1–2% of couples trying to conceive, with 50% remaining unexplained. Meta-analyses suggest LIT improves pregnancy outcomes for RM couples. However, results are conflicting due to differing criteria and protocols. This study evaluates low dose LIT effectiveness in patients with unexplained RM and Th1/Th2/Treg paradigm disorders. Method: Self-controlled, prospective study of 23 RM patients receiving partner lymphocyte immunization from August 2021 to October 2022, with [Formula: see text]3 miscarriages less than 12 weeks when endometrium at ET was [Formula: see text]8mm and PGT embryos were used. Patients with abnormal Th1/Th2/Treg cell proportions and biomarkers were treated with paternal lymphocytes twice before embryo transfer (ET) and once post-pregnancy confirmation. Results: Significant decrease in Th1 and increase in Th2 cytokines like TNF-a and IFN-g and significantly increase in Treg cells and TGF-b noted and blocking antibodies detected in all patients after LIT therapy. 20/23 (87%) post LIT conceived and 4 delivered healthy full-term babies (17%) and 3 patients have yet to undergo ET. 48% (11/23) uneventful ongoing pregnancies crossed [Formula: see text]14 weeks. 3 patients had miscarriages (13%). 1 patient (4%) did not conceive. 1(4%) conceived spontaneously ([Formula: see text]25 wks) and 1(4%) opted to try to conceive naturally. Cumulative uneventful pregnancy outcome 65%. Conclusion: LIT was associated with high live birth rates, especially in women with RM. It not only ameliorates patient’s cellular immune function, but also further increases patient’s pregnancy success rate with high safety, which is worthy of clinical application and promotion. Being small size self-controlled study, this result needs to be validated with large we’ll planned RCTs. LIT may be considered a safe and effective treatment for RM/RIF in IVF patients in individual cases based on immunoprofiling (Th1/Th2/Treg paradigm disorders), after ruling out other potential causes of RM or RIF.